The present invention relates to a caster brake system having a connection frame and rollers both of which are stopped in a braking operation.
A conventional stroller or shopping cart having casters generally equipped with a brake system for the wheels and generally a stop rod is inserted into the rim of the wheel to stop the shopping cart. Nevertheless, this conventional brake system can only stop the wheel but the frame which is rotatably connected to the wheel so that if the shopping cart moves along a downward slope, even if the wheels are stopped, the frames could rotate an angle and this results in falling of the goods on the cart. Another well-known brake system is to shift a brake bar to touch the outer surface of the wheel. This accelerates the worn of the wheel and the inherent problem is not improved.
The present invention intends to provide a caster brake system wherein the frame connected to the wheel is held in position when the wheel is stopped.
In accordance with one aspect of the present invention, there is provided a caster brake system that comprises a connection unit having a connection plate for connected with a cart or a stroller. A tubular member is connected to an underside of the connection plate so as to receive an upper cam that is rotatably received therein and a lower cam. The upper cam has first protrusions on an underside thereof and the lower cam has second protrusions on a top thereof. The lower cam is moved downward when a peak of each of the first protrusions contacts a peak of the second protrusion corresponding thereto. A disk is connected to an underside of the lower cam and has teeth on an outer periphery thereof.
A frame unit has a frame having an open top so as to receive the lower cam and a hole is defined through a bottom of the frame. A plurality of notches is defined in an inner periphery of the hole so as to match with the teeth of the disk when the disk is moved toward the hole. Two plates are connected to an underside of the frame and two wheel support arms extend from the two plates.
A braking unit has a pushing member pivotably located between the two plates and a first end of the pushing member can be pushed by the underside of the lower cam. A braking member is pivotably mounted to the two plates and a first end of the braking member can be pushed by a second end of the pushing member so that a second end of the braking member can stop the wheel of a wheel unit connected to the wheel support arms.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.